A 42-year-old male presents with vomiting and diarrhea for 2 days, and confusion and restlessness for half a day. On examination: BP 110/70 mmHg, delirium, moderate scleral icterus, multiple spider angiomas on the neck, no abnormalities in heart and lungs, soft abdomen, liver not palpable below the costal margin, spleen 3 cm below the costal margin, ecchymosis at the puncture site of the upper limb. Hb 90g/L, WBC 3.2×10⁹/L, blood glucose 7.0 mmol/L, glycosuria (+), ketonuria (-), urine microscopy (-). The most likely diagnosis is: